1 /*
   2  * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 package org.graalvm.compiler.replacements.test;
  24 
  25 import org.junit.Test;
  26 
  27 import org.graalvm.compiler.nodes.StructuredGraph;
  28 import org.graalvm.compiler.replacements.StringSubstitutions;
  29 import org.graalvm.compiler.replacements.nodes.ArrayEqualsNode;
  30 
  31 import jdk.vm.ci.code.InstalledCode;
  32 import jdk.vm.ci.meta.ResolvedJavaMethod;
  33 
  34 /**
  35  * Tests {@link StringSubstitutions}.
  36  */
  37 public class StringSubstitutionsTest extends MethodSubstitutionTest {
  38 
  39     public void testSubstitution(String testMethodName, Class<?> intrinsicClass, Class<?> holder, String methodName, boolean optional, Object[] args1, Object[] args2) {
  40         ResolvedJavaMethod realMethod = getResolvedJavaMethod(holder, methodName);
  41         ResolvedJavaMethod testMethod = getResolvedJavaMethod(testMethodName);
  42         StructuredGraph graph = testGraph(testMethodName);
  43 
  44         // Check to see if the resulting graph contains the expected node
  45         StructuredGraph replacement = getReplacements().getSubstitution(realMethod, -1);
  46         if (replacement == null && !optional) {
  47             assertInGraph(graph, intrinsicClass);
  48         }
  49 
  50         // Force compilation
  51         InstalledCode code = getCode(testMethod);
  52         assert optional || code != null;
  53 
  54         for (int i = 0; i < args1.length; i++) {
  55             Object arg1 = args1[i];
  56             Object arg2 = args2[i];
  57             Object expected = invokeSafe(realMethod, arg1, arg2);
  58             // Verify that the original method and the substitution produce the same value
  59             assertDeepEquals(expected, invokeSafe(testMethod, null, arg1, arg2));
  60             // Verify that the generated code and the original produce the same value
  61             assertDeepEquals(expected, executeVarargsSafe(code, arg1, arg2));
  62         }
  63     }
  64 
  65     @Test
  66     public void testEquals() {
  67         if (!Java8OrEarlier) {
  68             // StringSubstitutions are disabled in 1.9
  69             return;
  70         }
  71 
  72         final int n = 1000;
  73         Object[] args1 = new Object[n];
  74         Object[] args2 = new Object[n];
  75 
  76         // equal strings
  77         String s1 = "";
  78         String s2 = "";
  79         for (int i = 0; i < n / 2; i++) {
  80             args1[i] = s1;
  81             args2[i] = s2;
  82             s1 = s1 + "0";
  83             s2 = s2 + "0";
  84         }
  85 
  86         // non-equal strings
  87         s1 = "";
  88         s2 = "";
  89         for (int i = n / 2; i < n; i++) {
  90             args1[i] = s1;
  91             args2[i] = s2;
  92             s2 = s1 + "1";
  93             s1 = s1 + "0";
  94         }
  95 
  96         testSubstitution("stringEquals", ArrayEqualsNode.class, String.class, "equals", false, args1, args2);
  97     }
  98 
  99     @SuppressWarnings("all")
 100     public static boolean stringEquals(String a, String b) {
 101         return a.equals(b);
 102     }
 103 
 104 }